Preventing an exterior wall for an addition from interacting with wall for existing structure.

[h82fail]

I did my best recreating my 100yr old 2 story sold brick home. 

 

Created wall types for each story:

Basement is a concrete pony wall, with brick 3 courses thick above.

1st floor is a wall 3 courses thick, with interior framing and drywall surfaces 

2nd floor is a wall 2 courses thick, same interior build out.

 

Modeled on its own everything works great, and the interior frames out correctly.

 

The problem comes in when I try to build additions, every attempt causes weird things to happen on the 1st and 2nd stories.

How can I stop the new wall from changing the old?

 

.

[GeneDavis]

I got the no-posted-plan blues.  

 

Hey @h82fail, learn how to zip or shrink the plan file so it is under 15 bigs, then close Chief, and attach here to a post.  If it's huge, it's likely so because it's full of symbols.  Strip it of all save the structure. Windows and doors are OK.

 

And where'd "fail" come from?  Wouldn't you rather be a winner with this software?

[h82fail]

Had a feeling I should have posted the plan.

 

Mocking up a simple demo using an old simple version of my house to post; Noticed one file was doing it and another not. Identical files except one had a roof.

 

Deleted the roof planes and framing from the one and it stopped building the funny walls when I added an addition.

Auto-building a new roof over the house with an addition already in place works without funny walls.

 

Should have known it was something with the roof, noticed auto-generating 'attic walls" in floors above those weird ones when they appeared.

 

Edit: Alias read as "Hate to fail"

[KenL-sdd]

Post the  plan please